Lesson 19: Environmental Pollution PDF

**Урок 19. Загрязнение окружающей среды** **Environmental pollution** Pollutants emitted in the United States, particularly from the combustion of fossil fuels, have led to the development of many pressing environmental problems. Natural gas, emitting fewer harmful chemicals into the atmosphere th...

**Урок 19. Загрязнение окружающей среды** **Environmental pollution** Pollutants emitted in the United States, particularly from the combustion of fossil fuels, have led to the development of many pressing environmental problems. Natural gas, emitting fewer harmful chemicals into the atmosphere than other fossil fuels, can help to mitigate some of these environmental issues. These issues include: * Greenhouse Gas Emissions* * Smog, Air Quality and Acid Rain* * Pollution from the Transportation Sector* **Greenhouse Gas Emissions** Global warming, or the 'greenhouse effect' is an environmental issue that deals with the potential for global climate change due to increased levels of atmospheric 'greenhouse gases'. There are certain gases in our atmosphere that serve to regulate the amount of heat that is kept close to the earth's surface. Scientists theorize that an increase in these greenhouse gases will translate into increased temperatures around the globe, which would result in many disastrous environmental effects. **Power Plants Contribute to the Emission of Greenhouse Gases** The principle greenhouse gases include water vapor, carbon dioxide, methane, nitrogen oxides, and some engineered chemicals such as chlorofluorocarbons. The reduction of greenhouse gas emissions has become a primary focus of environmental programs in countries around the world. Because carbon dioxide makes up such a high proportion of U.S. greenhouse gas emissions, reducing carbon dioxide emissions can play a pivotal role in combating the greenhouse effect and global warming. The combustion of natural gas emits almost 30 percent less carbon dioxide than oil, and just under 45 percent less carbon dioxide than coal. **Smog, Air Quality and Acid Rain** Smog and poor air quality is a pressing environmental problem, particularly for large metropolitan cities. Smog, the primary constituent of which is ground level ozone, is formed by a chemical reaction of carbon monoxide, nitrogen oxides, volatile organic compounds, and heat from sunlight. As well as creating that familiar smoggy haze commonly found surrounding large cities, particularly in the summer time, smog and ground level ozone can contribute to respiratory problems ranging from temporary discomfort to long-lasting, permanent lung damage. The use of natural gas does not contribute significantly to smog formation, as it emits low levels of nitrogen oxides, and virtually no particulate matter. For this reason, it can be used to help combat smog formation in those areas where ground level air quality is poor. **Acid rain** is another environmental problem that affects much of the Eastern United States, damaging crops, forests, wildlife populations, and causing respiratory and other illnesses in humans. Acid rain is formed when sulfur dioxide and nitrogen oxides react with water vapor and other chemicals in the presence of sunlight to form various acidic compounds in the air. Since natural gas emits virtually no sulfur dioxide, and up to 80 percent less nitrogen oxides **Pollution from the Transportation Sector -- Natural Gas Vehicles** The transportation sector (particularly cars, trucks, and buses) is one of the greatest contributors to air pollution in the United States. Emissions from vehicles contribute to smog, low visibility, and various greenhouse gas emissions. According to the Department of Energy (DOE), about half of all air pollution and more than 80 percent of air pollution in cities are produced by cars and trucks in the United States. Currently, automobile manufacturers are under pressure to produce more environmentally friendly vehicles. Natural gas can be used in the transportation sector to cut down on these high levels of pollution from gasoline and diesel powered cars, trucks, and buses. Natural gas vehicles represent a growing segment of the transportation sector. According to the Natural Gas Vehicle Coalition, the use of natural gas for vehicles doubled between 2003 and 2009. Over 100,000 natural gas vehicles are currently on US roads. A large portion of those vehicles are transit buses, which account for nearly 62 percent of all natural gas vehicles. Natural gas is the cleanest of the fossil fuels, and thus its many applications can serve to decrease harmful pollution levels from all sectors, particularly when used together with or replacing other fossil fuels.